Factors Affecting the Development of Coronary Heart Disease.
Factors Affecting the Development of Coronary Heart Disease Heart is a muscle, like any muscle it requires a constant supply of nutrients such as oxygen and glucose to function. These nutrients are carried to the heart via the coronary arteries. Coronary heart disease (CHD) is the narrowing and clogging up of these arteries. If the coronary arteries get partly blocked, it causes the part of the heart which it was supplying, to respire anaerobic ally due to lack of oxygen, lactic acid is produced, causing the muscle cells to get cramp. This cramp is associated with chest pains called angina, which is relieved by rest. If the coronary arteries become fully blocked the part of the muscle which the arteries where supplying dies, this is called a heart attack or myocardial infarction. Both of these forms of heart disease occur due to narrowing or clogging up of the coronary arteries bought about as a result of arteriosclerosis. 'Arteriosclerosis, or hardening of the arteries is the disease process which leads to CHD' (biological sciences review) some hardening is thought to occur due to old age and hence older you are the higher the chance there is for you to develop heart disease. But 'many scientists think that arteriosclerosis begins with damage to the innermost layer of the artery wall' (www.americanheart.org) possibly bought about by a blow to the chest for example, harmful
Experiment to Compare Stomata Density in Different Dicotyledonous
Experiment to Compare Stomata Density in Different Dicotyledonous Aim: To investigate if stomata density on leaves in different dicotyledonous plants is effected by there country/ eco-system of origin. I will also compare the upper and lower epidermis stomata density to see were it lies. Information on stomata and Hypothesis Based Upon this Information: Diagram 1: Structure of a leaf. The lower and upper epidermis along with the stem of a plant may contain stomata. These are openings through which gases are exchanged with the atmosphere and water is lost, this is called transpiration. Carbon dioxide is need in the process of photosynthesis. Carbon dioxide is diffused in through the stomata for photosynthesis and some carbon dioxide is produced through respiration along with the production of water which transpires out. These openings are surrounded by specialized crescent shaped guard cells, which changes their size and shape to change the size of the stomatal openings. This regulates the gas exchange e.g. open more gas exchange, closed no gas exchange. These guard cells have different stimulus to active or deactivate the openings; light, CO2 concentration, humidity and wind speed. The epidermis is covered with a waxy coating called the cuticle, which functions as a waterproofing layer and which helps to reduces water loss from the plant surface through evaporation.
An Investigation to determine the Water potential of Potato cells.
An Investigation to determine the Water potential of Potato cells Baldeep Bains Hypothesis and background information The cells that are to be used in this investigation will be of a white potato; parenchyma cells. These cells are large, thin-walled and usually have a large vacuole, which holds water, and are filled with sap, 'a solution of ions, sugars and enzymes capable of digesting proteins'. These substances are the solutes that will affect the water potential of the potato cells. Food storage in the form of starch grains is the main function of potato tuber cells. The plasma membrane that bounds a cell is partially permeable; it allows only small molecules such as water, to pass through. Potato cells also have cell walls; these have a rigid lattice structure but are freely permeable. Visit coursework fa in fa fo fa for fa more project fa Do fa not fa redistribute Osmosis is defined as the movement of water molecules from a region of higher water potential to a region of lower water potential through a partially permeable membrane.cofe fer sefefew orfe fek infe fofe fe; Water potential is a measure of the ability of water molecules to move from one region to another. The more water molecules there are per volume of the cell the more likely that by random movement they will collide with the cell's plasma membrane, and travel out of it. Pure water has a ?w of 0. As all
Factors Affecting Osmosis.
FACTORS AFFECTING OSMOSIS AIM The aim of this experiment is to investigate the factors affecting osmosis. I have chosen to investigate the effect varying concentration of sucrose solution has on the amount of osmotic activity between the sucrose solution and a plant cell. The plant cell I have chosen to use is a potato tuber from which I plan to cut potato chips of equal length which I will place in test tubes filled with varying concentrations at equal volumes of sucrose solution. After a set amount of time I will remove the potato chips and record the change in length. BACKGORUND KNOWLEDGE High water potential is a solution which has a high concentration of water and a low concentration of solute (e.g. sugar, sucrose or salt) or no solute at all. Therefore it can either be a very dilute solution of something like sucrose or pure water, however in each case there is a lot of water. Whereas low water potential is the opposite of high water potential being a solution of low concentration of water and high concentration of solute (sugar, sucrose or salt). Hence it can be a concentrated solution of something like sucrose, however in this case there is much less water. When to solutions one of high water potential and one of low water potential are divided by a semi-permeable membrane water molecules will move from the solution of high water potential through the partially
Determine the water potential of potato tuber cell with the varying affect of solute concentration
:)Determine the water potential of potato tuber cell with the varying affect:) :)of solute concentration:) Introduction:) This investigation will try to determine the water potential of potato tuber cells. This will be carried out by using a potato cylinder and bathing it in different solutions of solute with different molarities and distilled water, which is pure. We will be able to find the water potential of the potato tuber cell by finding on the graph the equilibrium point where no water enters or leaves the potato. Osmosis has a very important role in this experiment. It is safe to say that osmosis is a unique type of diffusion, however only concerning with water molecules when they pass through a partially permeable membrane. When talking about the components of osmosis, the solvent (the water) and the solute (the sugar) added together make up the solution. In osmosis we always have a partially permeable membrane (the potato). It is known as this because it only allows certain molecules pass through like in our case the water molecules, just like a membrane in real life. Looking at the diagram below, we can see that sample 1 has a lower concentration of solute molecules which means it is a more dilute solution since there is a higher concentration of water molecules. Sample 2 is more concentrated since there are more solute
Investigating the effect of Sucrose Concentration on the Rate of Osmosis in Potato Chips.
G.C.S.E Science: Investigating the effect of Sucrose Concentration on the Rate of Osmosis in Potato Chips Sophie Chapman 25th March 2003 Aim: I shall carry out a sequence of independent experiments in order to investigate how the rate of osmosis in a potato chip is affected when the concentration of sucrose solution is varied. Apparatus: 300ml Sucrose concentration 300ml Distilled Water 2 x 100ml beaker 1 x 100ml Measuring Cylinder 1 x Potatoes 1 x Forceps (Tweezers) 1 x Scalpel Chipper 12 x Polystyrene Cups 1 x Stop - clock Tissues 12 x Sticky Labels 1 x Pen 1 x Calculator 1 x Ruler (measuring mm) 1 x Balance 1 x Polythene Food Bag Cardboard Apparatus Justification: To complete the experiment, I need 300ml distilled water and 300ml sucrose concentration as I intend to carry out 12 tests (using 6 different volumes but each shall be repeated twice) each using a 100ml of liquid whether it be pure water, pure sucrose concentration or a solution containing both. I will detail about the exact volumes of water and sucrose concentration that I want to use in each experiment, in the written procedure. I shall use varied amounts of sucrose solution for each test in order to adjust the concentration - a solution containing more sucrose has a greater concentration than a solution containing less sucrose solution. It is essential that the concentrations be
HSC Module-Blueprint of Life
9.3 - Blueprint of Life: . Evidence of evolution suggests that the mechanisms of inheritance, accompanied by selection, allows change over many generations: * Outline the impact on the evolution of plants and animals of: * Changes in the physical conditions in the environment: * Changes in the chemical condition in the environment: * Competition for resources: - Evolutionary theory states that all organisms have developed from previous organisms and that all living things have a common ancestor in some initial form of primitive life. - It also states that all organisms are fundamentally similar because their basic chemistry was inherited from this very first organism. - Changes in the Physical Environment: * The Earth has continually changed since life first evolved. * Various changes in sea levels, the splitting of the continents and great changes in climate are just some of the environmental changes that life on Earth have had to cope with, or become extinct. * Changes in the environment force species to either die out, or survive and diversify. * An Example - The Peppered Moth: > Prior to the Industrial Revolution of the late 18th Century, the majority of the Peppered moths were light coloured. They survived better as they could camouflage against the white lichen on the trees. > Post-revolution, the pollution caused the trees to blacken with soot. The trees
Investagating the Action of the Enzyme Catalase On the Surface Area of a Potato.
INVESTAGATING HOW INCREASING THE SURFACE AREA OF A POTATO AFEECTS THE AMOUNT OF OXYGEN PRODUCED AIM: My aim in this investigation is to examine how the amount of oxygen produced is affected by increasing the surface area of a potato (increasing the enzyme catalase in the experiment). I will be changing the surface area of a potato and observe how long it takes the oxygen to produce as I increase the surface area of the potato to produce oxygen. The substrate I will be using will be hydrogen peroxide and the biological catalyst will be the potato. VARAIBLES: In this investigation, I will increase the enzyme catalase in the experiment by increasing the surface area of the potato, and observe how it affects the amount of hydrogen peroxide decomposed, producing oxygen at the end of the reaction. The main variables in this investigation that affect the rate at which hydrogen peroxide is broken down are, the concentration of the hydrogen peroxide, the quantity of the hydrogen peroxide solution used, the temperature of the solution, the time at which the experiment is carried out for, the pH value of the catalyst and the surface area of the potato used. If the concentration of the solution is high, more hydrogen peroxide will be decomposed faster producing more oxygen. This is because if the concentration of the reactant is high and the reactants are more concentrated, then
Should people with diabetes 2 receive medical treatment?
Finn O Hurley Should people with Type 2 Diabetes receive expensive medical treatment? There are two types of diabetes type 1 and 2. Type 2 diabetes, the topic of this essay, is typically linked to diet. So before discussing whether people with type 2 diabetes should receive expensive medical treatment I will begin by discussing what is regarded as comprising a healthy diet. The Food Standards Agency in Britain recommends that people eat a certain proportion of foods from different food groups each day. The human body processes chemicals through different types of reaction and then distributes them around the body for use or storage. These chemicals can be divided into two broad groups: macronutrients that we need to eat often in quite large amounts, and micronutrients that are needed in smaller amounts. Three major macronutrients are essential to living organisms: proteins, fats and carbohydrates which I will discuss first.. Proteins are complex organic compounds and their basic structure is a chain of amino acids. Every cell in the human body contains protein and it is needed in the diet to help the body repair cells and make new ones through the process of mitosis. It is also vital for growth and development during childhood, adolescence, and pregnancy. Foods containing protein fall into two groups, complete or incomplete proteins. Complete proteins consist of
Investigating the effect of four antibiotic agents on gram positive and gram negative bacteria.
Investigating the effect of four antibiotic agents on gram positive and gram negative bacteria Aim To find out how four antibiotic agents- Penicillin G, Streptomycin, fresh garlic and odourless garlic- effect gram-positive and gram-negative bacteria. The two different bacteria used will be Bacillus subtilis and Escherichia coli. After transferring the antibiotics to the bacteria I will be able to look for zones of inhibition in the bacteria where the antibiotic agents were placed. Scientific knowledge & understanding Bacteria are prokaryotes, which means they are organisms that lack a nuclei and are a lot smaller in volume than Eukaryotes (animals, plants, fungi & protoctists), on average only 0.5-5 m in diameter. Bacteria are a lot simpler in their structure. Structures always found in bacteria include a cell wall, plasma membrane, cytoplasm, ribosomes and circular DNA. Other structures that are present in some bacteria can be shown in the diagram below. Bacteria can be found almost anywhere as different types have different optimum temperatures e.g. Thermophilic bacteria work best at temperatures above 45 C whereas Psychrophilic bacteria grow best at temperatures below 20 C. Bacteria can also be identified by their shape. Spherical bacteria are called cocci, bacteria that have a rod like shape are known as bacilli, corkscrew shaped bacteria are called spirilla and
